1. Field of the Invention
The invention relates to an adapter for a precision inspection instrument for determining the angular alignment of a precisely supported roller, such as those employed in a printing press. These rollers may also be employed in the production of films, foils, paper webs or thin sheets in other machines.
2. Description of Related Art
It has been suggested that a printing press be modified in order to check its rollers to ensure that the axes or axis pieces of the rollers are provided with an accurately oriented end face, or are provided with an adapter, produced in a highly precise manner, which extends in the axial direction of a roller. On the roller end faces or on an adapter connected to the roller, at least one highly accurate operating angle inspection device, for example, one employing optical gyroscopes, is mounted, and the inspection device acts in two dimensions such that the components of the angular alignment of the roller are determined.
This process however requires either extremely precise manufactured roller end faces or other types of roller surfaces which can be prepared only with very great effort. However, even this process does not guarantee that in the presence of a precisely aligned axis of rotation of a roller that the surface is still exactly aligned. This is due to the fact that irregularities, such as parallel displacements, skew positions, or other geometrical eccentricities, exist in the cylinder-symmetrical axis relative to the axis of rotation of the roller.
An alternate approach is to position a precision inspection instrument for determining the orientation of rollers, which have been manufactured with high precision, directly on a roller. This approach has certain risks since fine furrows or scratch traces on the roller cannot be prevented from the contact of the instrument with the polished surface of the roller.
The above-mentioned problem is solved in accordance with this invention by constructing a device which can be placed on the roller to be checked with virtually no direct mechanical contact with the roller. The device uses a high pressure fluid, preferably a compressed air means, and relies on the principles associated with a fluid cushion. The high pressure fluid or compressed air cushions can be produced adjacent to surfaces having a defined contour, such as a roller. However, high pressure fluid or compressed air cushions can also be employed in conjunction with surfaces which can be variable through the use of an adjustment device in order that mating of the device to different rollers can be accomplished.
In order to determine the orientation of a roller, a suitable precision inspection instrument, for example, a precision instrument based on utilizing several high-precision laser gyroscopes, is provided with a foot or an adapter which is provided with high pressure fluid or compressed air to create a fluid cushion which allows the precision instrument to float on the surface of a roller at a small, specifically determined and adjustable distance. This foot or adapter has a plurality of discharge nozzles which are located in a contoured surface of the adapter, preferably a concave, arched surface. When these nozzles are supplied with acceptably high enough air pressure, or optionally, with an acceptably high pressure liquid or liquid-gas mixture, the foot or the adapter can be placed on the roller employing a fluid cushion without direct mechanical contact with the roller surface. It is also advantageous that the foot or the adapter be relatively easily moved over the roller, both in the axial direction and around the roller periphery. Depending on the size of the adapter or the foot, as well as depending on the attained floating distance, the fluid or air consumption can be several liters per second. In that situation, it is advisable to make the compressed air or high pressure fluid available close to the foot or the adapter through the use of high pressure fluid tanks or a large, portable compressor if the tank supply is not sufficient.